Vehicle



March 19, 1946. D. D. ORMSBY VEHICLE Original Filed May 10, 1943 2 Sheets-Sheet 1 IN VEN TOR. fiamldfi Ormsy Patented Mar. 19, 1946" VEHICLE Donald D. Ormsby, Buchanan, Mich., assignor to Clark Equipment Company, Buchanan, Mich.,

a corporation Original application May 10, 1943, Serial No.

Divided and this application October 28, 1943, Serial No. 508,014

Claims.

This invention relates to vehicles and more particularly is concerned with a vehicle of the multiple engine type in which an auxiliary or supplemental engine is provided for adding its power to that of the main or conventional engine when the latter engine is under load.

The present invention is a continuation of and an improvement over the invention disclosed in my co-pending application, Serial No. 256,947, filed February 17, 1939, and is a division of my co-pending application, Serial No. 486,445, filed May 10, 1943.

In vehicles of this type, as disclosed in said copending applications, the auxiliary engine is arranged to have its power connected through a lay shaft into the countershaft of the transmission connected to the main engine. The auxiliary engine is normally inoperative, but under suitable conditions is started and brought up to speed whereupon, through suitable overrunning clutch mechanism or the like, it is clutched to the lay shaft so that the torque from this auxiliary engine can be transmitted to the countershaft of the transmission for assisting in driving the vehicle. The present invention is concerned particularly with improvement in the connection between the auxiliary engine and the lay shaft, and one of the primary objects is to provide in this driving connection an overrunning clutch and fluid coupling to provide drive means after the booster engine is started and brought up to speed so that the additional power of this engine will be fed in gradually to the drive train of the vehicle. This eliminates the possibility of gear clashing or sudden and unreasonable strains upon the parts of the driving train of the vehicle.

Another feature of the present invention produced by the construction disclosed herein is to prevent any possible lock-up of the gears against the compression of the engine if the vehicle tends to roll rearwardly at a stop, since the fluid coupling relieves this back pressure and'thereby prevents such lock-up. This in turn facilitates shifting of the transmission gears when it is desired to again start the vehicle. Preferably, in a preferred form of the invention the fluid clutch is embodied in the flywheel housing of the auxiliary it is obvious that there must be a speed differential between the engine shaft and the driven member of the fluid coupling at all times that the auxiliary engine is not in operation. This is accommodated by the overrunning clutch which remains inoperative whenever the lay shaft is rotating at a speed greater than the speed of rotation of the driven element of the fluid coupling. However, as the auxiliary engine comes. upto speed the driving member of the fluid coupling imparts torque to the driven member and tends to bring this member up to speed. At such time as this driven member reaches a speed greater than that of the lay shaft, the overrunning clutch operates to lock the driven member to provide a positive drive from the fluid coupling into the lay shaft. When the auxiliary engine speed drops below that of the lay shaft theclutch disconnects the driving connection therebetween.

Other objects and advantages of the present invention will appear more fully from the following detailed description which, taken in conjunction with the accompanying drawings, will disclose to those skilled in the art the particular construction and operation of a preferred form of the present invention.

In the drawings:

Figure 1 is a plan view, partly diagrammatic, of the vehicle employing the present invention, and

Figure 2 is a sectional view through the fluid coupling and overrunning construction which couples the auxiliary engine to the drive train.

Referring now in detail to the drawings, in Figure 1 there is shown a vehicle chassis including the side rails 5 and the cross member 6. Secured to the forward end of the side rails 5 in any conventional .manner is the front axle assembly .1 and mounted between the rails in any conventional manner is the main engine 8 having the clutch housing 9 secured thereto, carrying the transmission I0 which has the gear shift lever l2 projecting therefrom. At the rear endof the side rails 5, mounted in any suitable manner as by springs 13', is a drive axle assembly l4 carrying the drive wheels l5. The drive axle assembly M includes a differential carrier I6, and extending from this carrier to the rear end of the transmission is the usual propeller shaft H.

The transmission is provided with a laterally off-set housing 18, carryinggears connected to the countershaft of the transmission in, and including a layshaft l9 extendinginto a clutch housing 20, secured to the flywheel housing 22 of the auxiliary engine 23. The engine 23 is sup- I sting.

ported in any suitable manner from the side rails of the cross member I, and is preferably disposed conditions selected by the operator and dependent upon the load of main engine C can be started and brought up to speed, and add its power to the layshaft l9 and through the gears in housing it to the countershaft of the transmission, whereby its torque is added to that of the main engine for driving the propeller shaft l1. Such a construction is especially desirable in vehicles carrying heavy loads, such as trucks, buses or the like where, under normal operations in flat country, the power of the main engine 8 alone is suf-- ficient'to maintain the desired road speed, and the booster engine power is utilized only when it is desired to haveadditional torque for carrying the load over hills or the like,- or for acceleration'when pulling away fmm a. stop in order to maintain, as far as possible, the maximum road speed.

For this reason, it is desirable in theinterest of economy that the auxiliary engine be entirely stopped when its power is not required, but be instantly available whenever additional power is required. Considering now in detail Figure 2 of the drawings, the lay shaft connection is preferable to a 'yoke '30, carried on the stub shaft I2 extendinginto the clutch housing 20 at the forward end ofthe booster engine. The clutch housing 20 in turn is piloted in andsecured to the flywheel housing 22 of the booster engine. The shaft 32 I is splined at its outer end to'receivethe hub 30. which also carries a pulley 31 for driving the water pump on the booster engine.

vides circulation of water to the booster engine at all times that the main'enginels operating, since the shaft is driven from the transmission l whether or not the booster engine is oper- The shaft 32 adjacent at its outer end is carried in bearings 34 supported in the bearing cap I secured to the clutch housing 20. At its inner end, the shaft 32 is enlarged to provide a cylindrical hub portion 38, extending over the hub 31 of a. shaft 38, piloted at itsopposite end by means This prohub 81. However, when hub 81 increases its speed of rotation beyond the speed of shaft 32 the connection is such that the spring expands, providing africtional engagement between the external surface of hub 31 and internal surface of .iiange 3! forming a frictional drive whereby termediate its ends it is provided with a radial flange portion 4!, which has piloted thereon and bolted thereto the driven element 48 of a fluid clutch. The driving element of this clutch comprises the member 41 having a hub portion bolted to the crank shaft 40 of the booster engine and carrying a, vertical flange 4| forming a seat for of the bearings 39 in the end 40 of the crank shaft of the boosterengine.- The hub portion of the shafttaicarries on-its external surface a coiled spring 42 which operates as an overrunning clutch to couple the shaft 32 to the shaft 38 whenever the speed of the shaft it exceeds that of shaft 32.

This spring clutch is of the type normally known as the L. G. S. clutch and the details of its operation are not believed necessary. Sumce it to say that ,it'operates as a one-way'overrunning clutch to lock the shafts l8 and 32 for conjoint rotation when the speed of rotation of shaft 38 tends toexceed that of shaft 12.

The clutch disclosed comprises the relatively heavy coils of the spring 42 and a section of the spring ismade of lighter coils and acts as an the bearings 4! in which the reduced end of shaft 88 is piloted. The driving element 4'! of the fluid-clutch carries at its outer periphery the starting gear 40 and also has bolted thereto the housing element ll which encloses the driven element 4!. The housing ll has a bearing seat portion 12 receiving the roller bearing assembly I3 which 'rotatably supportsthe hub portion of the shaft 32. The'housing BI is provided with a hub extension 54 Journalledby means of the roller bearings II in the end I! of the clutch housing 20. A suitable lubricant seal I! is provided between the shank portion of shaft 32 and the hub 54 to prevent the fluid in the coupling 48, 41

from escaping outwardly along shaft 32. v

In the operation of the construction thus far described, the shaft it normally rotates in accordance with the particular speed ratio selected in the transmission II, and when the booster engine is not operating, none of the other parts of the assembly thus far described rotates. However,

of auxiliary engine 23 is transmitted to the shaft 32 and, consequently, into the crank shaft of the transmission to add this torque to that of the main engine for driving the propeller shaft of the vehicle. 7

By theusc of the fluid coupling. it will be apparent that when the vehicle is stopped, if there is any tendency toward reverse rotation, th fluid coupling prevents the compression in the auxiliary engine from looking up the transmission gears, so that the operator will'nothave to overcome this pressure in shifting gears to again resumeforward drive. Furthermore, thefluid cou- Diing is cfdistlnct advantage in preventing any shock loads being transmitted to the shaft 82 and thus will cause the torque of the booster engine to be smoothly applied to the shaft I2 as the clutch 42 engages the hub 34.

It is therefore apparent that I have provided, by use of the fluid coupling and overrunning clutch construction herein disclosed, a means for 32 is rotating ata speed greater than that of 7 producing a smooth and effective coupling of the auxiliary engine into the drive train whenever the auxiliary engine comes up to a speed greater than that of the lay shaft which is sufficiently smooth due to the action of the coupling and clutch to prevent any clashing of gears or unnecessary strain upon the parts and which is effectively disconnected when the power of the auxiliary engine is not required. In addition, due to the use of a fluid coupling it is obvious that ther can be no positive lock-up which would prevent shifting of the transmission gears when the second engine is inoperative.

I am aware that various changes may be made in details of the present construction, and therefore do not intend to be limited except as defined by the scope and spirit of the appended claims.

I claim:

1. In a coupling for connecting an engin to a lay shaft, a fluid driving element, a fluid driven element having an enlarged annular hub portion, a shaft having an enlarged hub overlying said hub portion and radially spaced thereabout, a helical spiral spring interposed therebetween and acting as a one-way clutch, and means on the outer annular surface of said shaft hub forming a bearing support for said driving element.

2. The coupling of claim 1 further characterized in the provision of a hub on said driving element, and a projecting spindle on said driven element journalled in said hub.

3. Coupling means for connecting an engine to a shaft comprising a clutch housing receiving one end of said shaft, said shaft end having an enlarged annular hub, a fluid coupling including a driving element having an extended portion overlying said shaft hub and journalled in said housing, bearing means between said hub and extended portion, a driven element within said driving element having an annular hub portion extending into said shaft hub, helical spring means between said hub and hub portion acting as a oneway clutch therebetween, said shaft and hub portion having adjacent alined axial bores, and alinement means in said bores extending between said members.

4. A fluid coupling for connecting a power shaft and a driven shaft comprising a driving element connected to said power shaft and having an enclosing housing portion, a driven element enclosed thereby having a hub portion, one end of said hub portion being journalled in said driving element, the other end of said hub portion having an annular cylindrical surface and an axial counterbore, said driven shaft extending into said housing portion and having an enlarged cylindrical flange portion overlying said cylindrical surface, an axial counterbore in said driven shaft alined with said first counterbore, a helical spring between said surface and said flange portion providing a one-way clutch therebetween, and alinement pin means extending between said counterbores.

5. The coupling of claim 4 including anti-friction bearing means between said housing portion and said flange portion of said driven shaft.

DONALD D. ORMSBY. 

